Research On The Key Technology Of The Time Slot Interchange For DPSK Packets

With increasing capacity of the communication networks, network node subjected to the "electronic bottleneck" restrictions is no longer able to satisfy the large capacity and high speed data processing demand at all. All-optical networks based on phase modulation formats have become the research hotspot. This thesis focused on the time slot interchange for differential phase-shift keying (DPSK) signal packet. The main works of this thesis are as follows.Firstly, an in-depth study of nonlinear polarization rotation (NPR) in semiconductor optical amplifier (SOA) was conducted. Optical switch principle based on SOA’s NPR effect was researched with theoretical analysis and numerical simulations, which offered a solid theoretical foundation for applications based on this effect.Secondly, the mainly influencing factors of polarization deterioration were experimentally studied in SOA’s NPR effect, which is the first time to the best of our knowledge. The experimental results shown that the initial polarization state of the signal light has little influence on the linear polarization deterioration, however the SOA initial bias current and input optical power play the main roles on the linear polarization deterioration. Therefore, the SOA should work at large bias current and low input optical power in order to reduce the polarization deterioration impact.Finally, one level and four levels time slot interchange experimental systems for phase encoding format DPSK signal packet were set up. The 10 Gb/s DPSK signals were modulated and corresponding experimental research completed.The research result would have important reference value and significance to the development of the application systems such as optical switches, all-optical signal processing system based SOA’s NPR.